EBONY FINISH 13 



A block of wood with holes bored in it to contain dropping-bottles may be placed in 

 the upper left-hand drawer. In this way the stains are as accessible as if they encum- 

 bered the desk. It is advisable to paint the inside of this drawer black so that the 

 light may not cause the staining reagents to deteriorate. 



A very popular method of preparing the wooden surfaces of labora- 

 tory desks, sinks, and tables is the application of the so-called "acid- 

 proofing." This gives an ebony-like finish which is not affected by 

 strong acids. 



In using it the surface of the wood must be new (free of any varnish, oil, or paint, 

 if previously so coated the surface must be planed). 



Solution i 



Potassium chlorate 125 .o grams. 



Cupric sulphate 125 . o grams. 



Water 1000 . o c.c. 



Apply two coats of this solution at least twelve hours between applications. 

 When thoroughly dry apply two coats of solution No. 2. 



Solution 2 



Aniline oil 120.0 c.c. 



Hydrochloric acid 180.0 c.c. 



Water 1000.0 c.c. 



When the treated surface is thoroughly dry apply one coat of raw linseed oil with a 

 cloth. After this is dry wash with very hot soapsuds. 



An aspirating bottle on a shelf elevated 2 feet, with rubber tubing and glass 

 tip leading to a small aquarium jar or other desk receptacle, makes a good substitute 

 for a small sink and faucet. A Hofmann screw clamp on the rubber tube controls 

 the flow of water. 



Ordinary glass salt cellars will be found very useful, where the watch-glass is 

 employed. They may also be wrapped, sterilized, and used to contain fluids for 

 inoculating, etc. 



A glass-topped fruit jar or a specimen jar containing a disinfecting solution for con- 

 taminated slides, etc., should be on every working desk. A good solution is that of 

 Harrington (corrosive sublimate, -0.8; commercial HC1, 60.0 c.c.; alcohol, 400.0 

 c.c.; water, to 1000.0 c.c.). 



Disinfectant Solution. A very simple method of making a disinfec- 

 tant similar to lysol is to put one part of cresol or crude carbolic acid 

 and one part of soft soap in a wide-mouthed bottle over night. The 

 resulting compound (Liquor cresolis comp. U. S. P.) makes a perfect 

 solution with water and a 5% solution of this will be found at least 

 equal jto a 5% phenol solution. In addition to using as a desk jar dis- 

 infectant it is excellent for disinfecting faeces, sputum, etc. 



